A rapid and efficient one-pot synthesis of a series of four novel nuevamine aza-analogues
is described based on the oxidative Ugi-type reaction and aza-Diels–Alder reaction
as post-functionalization. A simple IBX-mediated oxidation of a secondary amine followed
by isonitrile α-addition and finally an aza-Diels–Alder cycloaddition provides the
desired compounds in excellent overall yields considering the short reaction time,
atom economy, and the molecular complexity of the final products. This protocol presents
a highly attractive procedure for the rapid generation of fused polyheterocycles.
Key words
one-pot synthesis - natural products - oxidation - oxidative Ugi reaction - aza-Diels–Alder
cycloaddition